Apollo 11 Moon Landing Site Seen in Unprecedented Detail

The clearest view yet of the famous Apollo 11 landing site on the moon was captured by a NASA spacecraft in orbit around our planet's natural satellite.

The agency's Lunar Reconnaissance Orbiter (LRO) zeroed in on Mare Tranquillitatis, or the Sea of Tranquility — the place where humans first touched down on the lunar surface on July 20, 1969. The new image from LRO captures amazing details of the historic site, even revealing the remnants of Neil Armstrong and Buzz Aldrin's first steps on the moon.

In the image, the astronauts' tracks are the dark regions around the Lunar Module that lead to and from various scientific experiments that were set up on the surface of the moon.

LRO's camera snapped the picture as the probe flew only 15 miles (24 kilometers) above the moon's surface. The image, which was released on March 7, provides the best look yet at humanity's first venture to another world, NASA officials said in a statement.

One of the experiments that can also be made out in the image is the Passive Seismic Experiment Package, which provided the first lunar seismic measurements and continued to return data for three weeks after the Apollo 11 astronauts departed from the moon.

The discarded cover of the Laser Ranging RetroReflector is also highlighted in the image. This experiment allows precise measurements to be collected from the moon to this day, NASA officials said. [Photos: New Views of Apollo Moon Landing Sites]

The astronauts' tracks also lead toward Little West crater, which is located about 164 feet (50 meters) east of the Lunar Module. This was part of an unplanned excursion, when Armstrong bounced over to get a look inside the crater, near the end of the 2.5 hours that the duo spent on the surface of the moon.

The new image also clearly shows how restricted Armstrong and Aldrin were in their exploration of the area. Interestingly enough, their tracks cover less area than a typical city block, according to NASA officials.

Later, during Apollo 12 and 14, the astronauts were given more time to spend on the surface, and on the Apollo 15, 16 and 17 missions, the crews were equipped with a Lunar Roving Vehicle that enabled them to explore beyond the landing site.

The Apollo 11 astronauts returned valuable rock samples from the Sea of Tranquility landing site that revealed the moon's fiery past for the first time. The samples showed that this region of the moon was once the site of volcanic activity, and that thin flows of lava had once flowed where Armstrong and Aldrin had roamed.

LRO has captured images of other Apollo landing sites before, including fascinating pictures that show tracks left by the Apollo 17 astronauts and their lunar rove

Cassini Spies Wave Rattling Jet Stream on Jupiter

ew movies of Jupiter are the first to catch an invisible wave shaking up one of the giant planet's jet streams, an interaction that also takes place in Earth's atmosphere and influences the weather. The movies, made from images taken by NASA's Cassini spacecraft when it flew by Jupiter in 2000, are part of an in-depth study conducted by a team of scientists and amateur astronomers led by Amy Simon-Miller at NASA's Goddard Space Flight Center in Greenbelt, Md., and published in the April 2012 issue of Icarus.

"This is the first time anyone has actually seen direct wave motion in one of Jupiter's jet streams," says Simon-Miller, the paper's lead author. "And by comparing this type of interaction in Earth's atmosphere to what happens on a planet as radically different as Jupiter, we can learn a lot about both planets."

Like Earth, Jupiter has several fast-moving jet streams that circle the globe. Earth's strongest and best known jet streams are those near the north and south poles; as these winds blow west to east, they take the scenic route, wandering north and south. What sets these jet streams on their meandering paths—and sometimes makes them blast Florida and other warm places with frigid air—are their encounters with slow-moving waves in Earth's atmosphere, called Rossby waves. 

In contrast, Jupiter's jet streams "have always appeared to be straight and narrow," says co-author John Rogers, who is the Jupiter Section Director of the British Astronomical Association, London, U.K., and one of the amateur astronomers involved in this study.

Rossby waves were identified on Jupiter about 20 years ago, in the northern hemisphere. Even so, the expected meandering winds could not be traced directly, and no evidence of them had been found in the southern hemisphere, which puzzled planetary scientists.

To get a more complete view, the team analyzed images taken by NASA's Voyager spacecraft, NASA's Hubble Space Telescope, and Cassini, as well as a decade's worth of observations made by amateur astronomers and compiled by the JUPOS project.

The movies zoom in on a single jet stream in Jupiter's southern hemisphere. A line of small, dark, v-shaped "chevrons" has formed along one edge of the jet stream and zips along west to east with the wind. Later, the well-ordered line starts to ripple, with each chevron moving up and down (north and south) in turn. And for the first time, it's clear that Jupiter's jet streams, like Earth's, wander off course.

"That's the signature of the Rossby wave," says David Choi, the postdoctoral fellow at NASA Goddard who strung together about a hundred Cassini images to make each time-lapse movie. "The chevrons in the fast-moving jet stream interact with the slower-moving Rossby wave, and that's when we see the chevrons oscillate."

The team's analysis also reveals that the chevrons are tied to a different type of wave in Jupiter's atmosphere, called a gravity inertia wave. Earth also has gravity inertia waves, and under proper conditions, these can be seen in repeating cloud patterns.

"A planet's atmosphere is a lot like the string of an instrument," says co-author Michael D. Allison of the NASA Goddard Institute for Space Studies in New York. "If you pluck the string, it can resonate at different frequencies, which we hear as different notes. In the same way, an atmosphere can resonate with different modes, which is why we find different kinds of waves."

Characterizing these waves should offer important clues to the layering of the deep atmosphere of Jupiter, which has so far been inaccessible to remote sensing, Allison adds. 

Crucial to the study was the complementary information that the team was able to retrieve from the detailed spacecraft images and the more complete visual record provided by amateur astronomers. For example, the high resolution of the spacecraft images made it possible to establish the top speed of the jet stream's wind, and then the amateur astronomers involved in the study looked through the ground-based images to find variations in the wind speed.

The team also relied on images that amateur astronomers had been gathering of a large, transient storm called the South Equatorial Disturbance. This visual record dates back to 1999, when members of the community spotted the most recent recurrence of the storm just south of Jupiter's equator. Analysis of these images revealed the dynamics of this storm and its impact on the chevrons. The team now thinks this storm, together with the Great Red Spot, accounts for many of the differences noted between the jet streams and Rossby waves on the two sides of Jupiter's equator. 

"We are just starting to investigate the long-term behavior of this alien atmosphere," says co-author Gianluigi Adamoli, an amateur astronomer in Italy. "Understanding the emerging analogies between Earth and Jupiter, as well as the obviously profound differences, helps us learn fundamentally what an atmosphere is and how it can behave."

New Images of Rhea

http://www.jpl.nasa.gov/news/news.cfm?release=2012-069&cid=release_2012-069&msource=12069#

Citizen Scientists Reveal a Bubbly Milky Way

A team of volunteers has pored over observations from NASA's Spitzer Space Telescope and discovered more than 5,000 "bubbles" in the disk of our Milky Way galaxy. Young, hot stars blow these bubbles into surrounding gas and dust, indicating areas of brand new star formation.  

Upwards of 35,000 "citizen scientists" sifted through the Spitzer infrared data as part of the online Milky Way Project to find these telltale bubbles. The volunteers have turned up 10 times as many bubbles as previous surveys so far.   

"These findings make us suspect that the Milky Way is a much more active star-forming galaxy than previously thought," said Eli Bressert, an astrophysics doctoral student at the European Southern Observatory, based in Germany, and the University of Exeter, England, and co-author of a paper submitted to the Monthly Notices of the Royal Astronomical Society. 

"The Milky Way's disk is like champagne with bubbles all over the place," he said.

Computer programs struggle at identifying the cosmic bubbles. But human eyes and minds do an excellent job of noticing the wispy arcs of partially broken rings and the circles-within-circles of overlapping bubbles. The Milky Way Project taps into the "wisdom of crowds" by requiring that at least five users flag a potential bubble before its inclusion in the new catalog. Volunteers mark any candidate bubbles in the infrared Spitzer images with a sophisticated drawing tool before proceeding to scour another image.   

"The Milky Way Project is an attempt to take the vast and beautiful data from Spitzer and make extracting the information a fun, online, public endeavor," said Robert Simpson, a postdoctoral researcher in astronomy at Oxford University, England, principal investigator of the Milky Way Project and lead author of the paper. 

The data come from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) and Multiband Imaging Photometer for Spitzer Galactic (MIPSGAL) surveys. These datasets cover a narrow, wide strip of the sky measuring 130 degrees wide and just two degrees tall. From a stargazer's perspective, a two-degree strip is about the width of your index finger held at arm's length, and your arms opened to the sky span about 130 degrees. The surveys peer through the Milky Way's disk and right into the galaxy's heart. 

The bubbles tagged by the volunteers vary in size and shape, both with distance and due to local gas cloud variations. The results will help astronomers better identify star formation across the galaxy. One topic under investigation is triggered star formation, in which the bubble-blowing birth of massive stars compresses nearby gas that then collapses to create further fresh stars. 

"The Milky Way Project has shown that nearly a third of the bubbles are part of 'hierarchies,' where smaller bubbles are found on or near the rims of larger bubbles," said Matthew Povich, a National Science Foundation Astronomy and Astrophysics Postdoctoral Fellow at Penn State, University Park, and co-author of the paper. "This suggests new generations of star formation are being spawned by the expanding bubbles."

Variations in the distribution pattern of the bubbles intriguingly hint at structure in the Milky Way. For example, a rise in the number of bubbles around a gap at one end of the survey could correlate with a spiral arm. Perhaps the biggest surprise is a drop-off in the bubble census on either side of the galactic center. "We would expect star formation to be peaking in the galactic center because that's where most of the dense gas is," said Bressert. "This project is bringing us way more questions than answers."     

In addition, the Milky Way Project users have pinpointed many other phenomena, such as star clusters and dark nebulae, as well as gaseous "green knots" and "fuzzy red objects." Meanwhile, the work with the bubbles continues, with each drawing helping to refine and improve the catalog.   

For those interested in counting bubbles and contributing to the Milky Way Project, visit the following link:www.milkywayproject.org . To learn of other citizen science-based efforts, check out the Zooniverse:https://www.zooniverse.org/ .

Saturn's Icy Moon Dione Has Oxygen Atmosphere

A NASA spacecraft circling Saturn has discovered a wispy oxygen atmosphere on the ringed planet's icy moon Dione, but you wouldn't want to live there. For one thing, you wouldn't be able to breathe — Dione's atmosphere is 5 trillion times less dense than the air at Earth's surface, scientists say.

Dione's atmosphere was detected by NASA's Cassini spacecraft, which spotted an ultra-thin layer of oxygen ions so sparse that it is equivalent to conditions 300 miles (480 kilometers) above Earth. On Dione, there is just one oxygen ion one for every 0.67 cubic inches (or one ion for every 11 cubic centimeters) of space, but it's still enough to qualify as an atmosphere, Cassini mission scientists announced Friday (March 2).

"We now know that Dione, in addition to Saturn's rings and the moon Rhea, is a source of oxygen molecules," Cassini team member Robert Tokar of the Los Alamos National Laboratory in New Mexico, who led the new study, said in a statement. "This shows that molecular oxygen is actually common in theSaturn system and reinforces that it can come from a process that doesn't involve life."

Dione is one of Saturn's smaller moons and is about 698 miles (1,123 km) wide. It orbits Saturn once every 2.7 days at a distance of about 234,000 miles (377,400 km) — roughly the same as that between Earth and its moon, according to a NASA description. [Photos: The Moons of Saturn]

The oxygen on Dione may potentially be created by solar photons or high-energy particles that bombard the Saturn moon's ice-covered surface, kicking up oxygen ions in the process, Tokar explained.  Another idea suggests that geologic processes on Dione could feed the moon's atmosphere, researchers added.

The study is detailed in a recent issue of the journal Geophysical Research Letters.

Dione is by no means the only rocky body with an atmosphere in our solar system. Thick atmospheres cover the planets of Earth, Venus and Mars, as well as Saturn's largest moon Titan.

A thin atmosphere on Saturn's moon Rhea — one similar to that of Dione — was also detected in 2010, NASA officials said.  That observation and the discovery of ozone on Dione by the Hubble Space Telescope led researchers to suspect it may host a thin atmosphere.

But it wasn't established for sure until the Cassini spacecraft used an instrument called a plasma spectrometer to detect the ionized oxygen on Dione during a close flyby in April 2011, when the probe flew within 313 miles (503 km) of the icy moon. The spacecraft detected an atmosphere made up of about 2,550 oxygen ions per cubic foot (or about 90,000 per cubic meter), researchers said.

"Scientists weren't even sure Dione would be big enough to hang on to an exosphere, but this new research shows that Dione is even more interesting than we previously thought," said Amanda Hendrix, the deputy project scientist for Cassini at NASA's Jet Propulsion Laboratory, Pasadena, Calif., who did not participate in Tokar's study. "Scientists are now digging through Cassini data on Dione to look at this moon in more detail."

Dione was discovered in 1684 by astronomer Giovanni Cassini, after whom the Cassini spacecraft is named. The moon is named after the Greek goddess Dione, who the ancient Greek poet Homer described as the mother of the goddess Aphrodite, NASA officials explained.

NASA launched the Cassini mission in 1997 and it has been orbiting Saturn since its arrival at the ringed planet in 2004. The mission, which is a joint effort by NASA and the space agencies of Europe and Italy, has been extended several times, most recently until 2017.

Dark Matter Left Behind After Galaxy Collision?

A composite image of the merging galaxy cluster Abell 520 shows the distribution of dark matter, galaxies, and hot gas. The orange picture shows the starlight from galaxies, while the blue picture shows the location of most of the mass in the cluster, which is dominated by dark matter (the dark-matter distribution is derived from gravitational lensing measurements). The green image shows regions of hot gas, and the natural-color photo of the galaxies was taken with NASA's Hubble Space Telescope and with the Canada-France-Hawaii Telescope in Hawaii.

CREDIT: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)

Can Humans See 'Spooky' Quantum Activity?

Quantum physics deals with the realm of the very small, and most of us never expect to see the weird world it describes. But could we? Recently, scientist Geraldo Barbosa of Northwestern University designed an experiment to answer that question.

The quantum effect Barbosa is hoping to see is calledquantum entanglement, in which two or more particles can become "entangled" so that even after they are separated in space, when an action is performed on one particle, the other particle responds immediately.

A common experiment illustrating entanglement is to fire a laser at a special type of crystal. Occasionally a photon particle from the laser "splits" into two. The energy and momentum of the two new photons each add up to the value of the one originally fired.

These two "daughter" photons are entangled — if you look at the state of one photon, you know the state of the other, instantly. Einstein described this eerie connection as "spooky action at a distance."

Next, the physicists change the form of the laser beam in the experiment to create an image. They have found that the image isn't visible unless two detectors are able to "see" the photons at the same time.

While these physics experiments rely on detectors to "see" the photons and the resulting images, Barbosa foresees setting up an experiment in which a person's retinas would act as the detectors. [Stunning Photos of the Very Small]

Spooky action in the lab

The entangled photons have opposite polarization states: in other words, their waves are oriented differently. (On a quantum level, particles can behave like waves, and waves like particles.)

In these experiments when only one photon is detected, it could be in any polarization state and it can hit the detector at any time. That means scientists can't tell whether the photon hitting their detector is from the entangled duo. Without that knowledge, a person can't reconstruct the image these photons are meant to create.

But when both entangled photons are detected, you can figure out the photon's polarization state. Knowing one, you know both, and can recreate the image. The "spooky" part is that by observing either one of the photons you've eliminated all the other possibilities — both observed photons must have the polarization states you see. But how does the entangled photon "know" what state to be in? Relativity says that you can't have information travel faster than light. Observing entangled photons, though "forces" them into a certain state at the same time. [10 Effects of Faster-Than-Light Discovery]

Essentially, the information in both photons is added to recreate the original image. This experiment has been done many times.

But what would happen if the two detectors were human retinas? Would a person see the higher-order image or just the classical one, the flash of light?

Ordinarily, we see things by perceiving the intensity of the light in several wavelengths. Mixing various wavelengths makes up all the various colors and saturations we perceive.

This situation would be different — if brains could see quantum effects like entangled photons, one would expect a different image when looking with one eye than with both. This is a deeper question than it may seem, because if people can see such images, it means our macroscopic brains can pick up subtle, microscopic quantum effects.

Next step in quantum vision

Barbosa said there are still difficulties with setting up such an experiment. One problem is the signal-to-noise ratio in human neurons. We can't perceive individual photons even though they hit our retinas, as it takes a certain number of photons hitting our eyes for our brains to interpret the signal as, for example, a flash of light.

In his paper, which is posted on the physics pre-print website arXiv, Barbosa notes that it is far from clear that one could generate enough photons to trigger a response from the human retina — at least seven photons are necessary to do that, and they would all have to be entangled.

Robert Boyd, professor of optics at the University of Rochester, said he doesn't see anything in principle wrong with the idea. "Even here, there are two possibilities," Boyd wrote in an email to LiveScience. "One is that the human brain simply does not work in the manner that Barbosa proposes. The other is that it does, but that the effect is so weak as to be unobservable."

Barbosa, meanwhile, said he has been thinking about this for a while —he did some of the first experiments with quantum images in his lab in 1994. And he sketches out some of the equipment that would be needed to make the experiment work, such as special goggles to get the photons to the right part of the retina.

"This would only indicate that the complex neural system is able to process quantum signals —an amazing feature," Barbosa wrote.